sketch out a plan and leave its completion to others instead of
having my heart in the welfare of the science, to which I had
devoted myself so long; in truth, it required no little
constancy, and even self-denial, to postpone the sweets of an
immediate success to the prospect of a slower, but more lasting,
reputation.

     Making plans is often the occupation of an opulent and
boastful mind, which thus obtains the reputation of a creative
genius, by demanding what it cannot itself supply; by censuring,
what it cannot improve; and by proposing, what it knows not where
to find. And yet something more should belong to a sound plan of
a general critique of pure reason than mere conjectures, if this
plan is to be other than the usual declamations of pious
aspirations. But pure reason is a sphere so separate and self-
contained, that we cannot touch a part without affecting all the
rest. We can therefore do nothing without first determining the
position; of each part, and its relation to the rest; for, as our
judgment cannot be corrected by anything without, the validity
and use of every part depends upon the relation in which it
stands to all the rest within the domain of reason.

     So in the structure of an organized body, the end of each
member can only be deduced from the full conception of the whole.
It may, then, be said of such a critique that it is never
trustworthy except it be perfectly complete, down to the smallest
elements of pure reason. In the sphere of this faculty you can
determine either everything or nothing.

     But although a mere sketch, preceding the Critique of Pure
Reason, would be unintelligible, unreliable, and useless, it is
all the more useful as a sequel. For so we are able to grasp the
whole, to examine in detail the chief points of importance in the
science, and to improve in many respects our exposition, as
compared with the first execution of the work.

     After the completion of the work I offer here such a plan
which is sketched out after an analytical method, while the work
itself had to be executed in the synthetical style, in order that
the science may present all its articulations, as the structure
of a peculiar cognitive faculty, in their natural combination.
But should any reader find this plan, which I publish as the
Prolegomena to any future Metaphysics, still obscure, let him
consider that not every one is bound to study Metaphysics, that
many minds will succeed very well, in the exact and even in deep
sciences, more closely allied to practical experience,4 while
they cannot succeed in investigations dealing exclusively with
abstract concepts. In such cases men should apply their talents
to other subjects. But he who undertakes to judge, or still more,
to construct, a system of Metaphysics, must satisfy the demands
here made, either by adopting my solution, or by thoroughly
refuting it, and substituting another. To evade it is impossible.

     In conclusion, let it be remembered that this much-abused
obscurity (frequently serving as a mere pretext under which
people hide their own indolence or dullness) has its uses, since
all who in other sciences observe a judicious silence, speak
authoritatively in metaphysics and make bold decisions, because
their ignorance is not here contrasted with the knowledge of
others. Yet it does contrast with sound critical principles,
which we may therefore commend in the words of Virgil:

     " Ignavum, fucos, pecus a praesepibus arcent. "
     "Bees are defending their hives against drones, those
     indolent creatures. "

                             * * * *
                                
                          PROLEGOMENA.
                                
  PREAMBLE ON THE PECULIARITIES OF ALL METAPHYSICAL COGNITION.

             Sect. 1: Of the Sources of Metaphysics

     If it becomes desirable to formulate any cognition as
science, it will be necessary first to determine accurately those
peculiar features which no other science has in common with it,
constituting its characteristics; otherwise the. boundaries of
all sciences become confused, and none of them can be treated
thoroughly according to its nature.

     The characteristics of a science may consist of a simple
difference of object, or of the sources of cognition, or of the
kind of cognition, or perhaps of all three conjointly. On this,
therefore, depends the idea of a possible science and its
territory.

     First, as concerns the sources of metaphysical cognition,
its very concept implies that they cannot be empirical. Its
principles (including not only its maxims but its basic notions)
must never be derived from experience. It must not be physical
but metaphysical knowledge, viz., knowledge lying beyond
experience. It can therefore have for its basis neither external
experience, which is the source of physics proper, nor internal,
which is the basis of empirical psychology. It is therefore a
priori knowledge, coming from pure Understanding and pure Reason.

     But so far Metaphysics would not be distinguishable from
pure Mathematics; it must therefore be called pure philosophical
cognition; and for the meaning of this term I refer to the